APPROACHES TOWARDS A CRITICAL EVALUATION AND UPDATE OF THE RED LIST OF SOUTH AFRICAN BUTTERFLIES JONATHAN BRADFORD BALL

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1 APPROACHES TOWARDS A CRITICAL EVALUATION AND UPDATE OF THE RED LIST OF SOUTH AFRICAN BUTTERFLIES JONATHAN BRADFORD BALL Thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Conservation Ecology at the University of Stellenbosch APRIL 2006 Supervisor: Prof H. Geertsema Co-supervisor: Prof M. J. Samways

2 Declaration I, the undersigned, hereby declare that the work contained in this thesis is my own original work and that I have not previously in its entirety or in part submitted it at any university for a degree... Signature Date ii

3 ABSTRACT Using the World Conservation Union s (formerly the International Union for the Conservation of Nature) IUCN 2001 categories and criteria, the conservation status of the South African butterfly fauna has been reassessed. This study includes an assessment of the 62 globally threatened South African taxa and 1 that has a marginal distribution in this region. The evaluation has been made using the first Red Data Book (RDB) on South African butterflies by Stephen & Graham Henning (1989) as a point of departure. In the seventeen years since the publication of this RDB, great political and environmental changes have taken place. The updated IUCN recommendations for adjusting the global categories and criteria for national Red Listing have also been taken into account. An analysis of the present South African butterfly species in regards to their changed taxonomy, further habitat degradation and present threats, extant IUCN Red List categorization and partially revised environmental law is presented. A precautionary rather than an evidentiary approach is used. A total of 63 butterfly taxa are Red Listed, which is 7.9% of the total butterfly fauna for South Africa, Lesotho and Swaziland (671 sp. and 129 ssp.). 81% of these Red Listed taxa are lycaenids. There is a considerable void in our present knowledge apropos the distribution, biology and ecology of most of the taxa. It is evident that some of the endemic butterflies with small distributions are under severe threat. Most of the threats appear to be synergistic. iii

4 UITTREKSEL Die bewaringsstatus van die Suid-Afrikaanse skoenlapper fauna is herbepaal deur gebruik te maak van die World Conservation Union s IUCN se kategorieë en criteria. Die evaluasie is gedoen deur die eerste Rooi Data Boek (RDB) oor Suid-Afrikaanse skoenlappers van Stephen en Graham Henning (1989) as n vertrekpunt te neem. In die vyftien jaar sedert die publisering van hierdie RDB het groot politieke en omgewing veranderinge plaasgevind. Die opgedateerde IUCN aanbevelings vir die aanpassing van die globale kategorieë en criteria vir nasionale Rooilysting is ook in ag geneem. Ingesluit in die studie is n evaluasie van 62 globaal bedreigde Suid-Afrikaanse taksa en 1 met n marginale voorkoms. n Ontleding van die huidige Suid-Afrikaanse skoenlapper spesies met betrekking tot hulle veranderde taksonomie, verdere habitat agteruitgang en huidige bedreigings, bestaande IUCN Rooi Lys kategorisasie en gedeeltelike hersiene omgewingswetgewing is gemaak. n Voorkomende eerder as n bewysbenadering is gebruik. n totaal van 63 skoenlapper taksa, wat 7.9% van die totale skoenlapper fauna vir Suid-Afrika, Lesotho en Swasieland (671 sp. en 129 ssp.) behels, word op die Rooi Lys geplaas. 81% van die Rooi gelyste taksa is lycaeniede. Daar is n aansienlike leemte in ons huidige kennis ten opsigte van die verspreiding, biologie en ekologie van al die skoenlapper taksa. Dit is duidelik dat sommige van die endemiese Suid-Afrikaanse soorte met klein areas van verspreiding ernstig bedreig word. Meeste van die bedreigings skyn sinergisties te wees. iv

5 ACKNOWLEDGEMENTS I would like to express my sincere appreciation for the assistance and advice given by the following people: Prof. Henk Geertsema (Department of Entomology, University of Stellenbosch) for acting as my primary supervisor, for ready access, advice, constructive counsel and criticism. Prof. Michael Samways (Department of Entomology, University of Stellenbosch). In particular, for assisting me with advice and reference material from his extensive library. Also for ready help in familiarising me with the workings of the IUCN s Species Survival Commission and the Red Listing process. Prof. Tim New, La Trobe University, Victoria, Australia, for most useful advice and information on threatened insects in Australia. Dr. Rienk de Jong, Naturalis, Leiden, the Netherlands, for valuable assistance on recent taxonomic changes in the Hesperiidae. Mr. Graham Henning, Johannesburg, for valuable input on the updated South African Red Data Listing of butterflies. Dr. Dave Edge, Knysna, for valuable information and opinions on the threatened butterfly biota of the south eastern portion of the Western Cape. v

6 Mr. Ernest Pringle, Bedford, for his valuable opinions of the Red Data listing of South African butterflies. Mrs. Margaret Sandwith, librarian at the Niven Library, Percy FitzPatrick Institute of African Ornithology, University of Cape Town. Mr. Alf Curle, Douglasdale, for valuable additional information on the Red Data listing of South African Butterflies. Dr. Mike Rutherford and Mr. Les Powrie of the National Botanical Institute, Kirstenbosch for information relating to the New Vegetation Map of South Africa, Lesotho & Swaziland. (Beta version 4.0, February 2004). Also for permission to use the SANBI map of the Biome Units of South Africa, Lesotho & Swaziland [Mucina et al. (eds)] Mr. Tony Brinkman, Cape Town, for much valuable information on the ecology and distribution of many at risk Western and Northern Cape taxa, for friendship, as well as hugely enjoyable scientific sampling outings. Mr. Renier Terblanche, Potchefstroom, for valuable information on threatened South African butterflies. Mr. Steve Woodhall, Durban, for advice and particularly for the vi

7 use of many of his outstanding images of South African butterflies. Last, but not least, my wife Carolynn, for making it all worthwhile. For her unflagging support, toleration and love. (There is probably a special place in heaven for the partners of entomologists!). vii

8 All true biologists deserve the coveted name of naturalist. The touchstone of a naturalist is his abiding interest in living Nature in all its aspects. Frederick G. Hopkins (1929 Nobel prize winner for Physiology and Medicine). Presidential address London Natural History Society, He was stimulated to study molecular biodiversity as a schoolboy, trying to extract colour from butterfly wings and isolating the substance explosively discharged by bombardier beetles (Brachinus explodens) (Campbell 2003). What sets worlds in motion is the interplay of differences, their attractions and repulsions. Life is plurality, death is uniformity. Octavio Paz ( ) Nothing endures but change. Heraclitus ( BC), quoted by Stern viii

9 CONTENTS ABSTRACT UITTREKSEL ACKNOWLEDGEMENTS iii iv v CHAPTERS: 1 GENERAL INTRODUCTION 1 2 HISTORICAL OVERVIEW OF THE RED DATA LIST 15 OF SOUTH AFRICAN BUTTERFLIES 3 USE OF THE ECOLOGICAL EMPHASIS ON BUTTERFLIES 23 4 OTHER ORGANISMS ASSOCIATED WITH BUTTERFLIES 39 AND THEIR INCLUSION AND/ OR PROTECTION IN A RED DATA LIST. THE HABITAT APPROACH 5 HABITAT APPROACH INCLUDES OTHER RED DATA SPECIES 43 6 HABITAT CONSERVATION OR HABITAT MANAGEMENT 47 7 LEGISLATION CONSTRUCTIVE OR IMPAIRMENT? 59 8 DETERMINISTIC AND STOCHASTIC FACTORS 69 CAUSING THE DECLINE OF SOUTH AFRICAN BUTTERFLIES 9 FUTURE POLICY RE RED DATA SPECIES A PROPOSED 2006 RED LIST OF SOUTH AFRICAN BUTTERFLIES CONCLUSIONS 303 APPENDICES (followed by references of appendices) 315 ABBREVIATIONS USED 458 ALPHABETIZED SPECIES LIST 459 ALPHABETIZED LIST OF COMMON NAMES 470 ix